The Black Book: Seven Deadly Sins - Chapter 20, C7 Forum

The Special Investigations Unit is a covert organisation that no-one in the city knows about, dedicated to investigating bizarre occurrences beyond the comprehension of the living. The Chief Zhao Yunlan isn’t a simple guy either, being the inheritor of the Guardian Order, he has always been a righteous conformist, excelling between realms of the living and the dead. While investigating a school suicide case, Zhao is attracted to the calm and reserved Professor Shen Wei, but the Professor seems to be rather fickle towards him…

- Description from Novelupdates

When encountering demons, a young man with two horns on his head, red hair reaching his waist, and an extremely handsome appearance leads the demons to the front.

Youdou: Actually, I really don’t want to be a master of monsters. This profession is completely useless. My ideal is to become a magic stick…, bah, it’s to become a great onmyoji.

All the monsters: My lord, wake up, you are the leader of the monsters yourself!

- Description from novelbuddy

The eldest daughter of the Yan family, Yan Jinyu, who has been missing for 16 years, has been found. She is brought back from an orphanage by her fiancé, the Second Master of the Yin family.

“I turned into a young dragon and was captured and raised by an Evil Dragon. As we spent more time together, I noticed that the way the Evil Dragon looked at me started to become increasingly odd. It seemed... he was raising me as if I were his wife!” Princess Lucia, transformed into a young dragon, wrote down her discovery with trembling hands in her notebook.